Pending:
- Adding explanations to the confirmation dialog:
- This is a 2-steps process
- The auto-confirm configuration option may have been set

I think highlighting that this is a 2-step process in the UX is a very important part of the blueprint, additional ideas in that area are also welcome.

Since I had to look it up initially... 'nova migrate' performs a "dead" migration on a server, essentially creating a snapshot of the drive, transferring it to a new server and rebooting. [0] The new host is selected by the scheduler. [1]

- Migrate and resize share a code path (as in, migrate is a special kind of resize or vice-versa...). When the migration begins, the default status messages are "Resize migrating", "Verify resize" etc which could be confusing. Ideally the UI should show migration-specific messages.

- Migrate/resize is a 2-step process. After the resize a resize-confirm or resize-revert command needs to be manually entered. This 2-steps process will need to be reflected in the UI.

Additionally there's an auto-confirm config option (resize_confirm_window) in Nova, which defaults to infinity. If it's set though, the migrate/resize will be automatically confirmed if no action is taken within that timeframe. I don't think we can access nova config options through the API (?) to tell the user about it, but we should at least give a warning that auto-confirm may be enabled (therefore they shouldn't wait too long if they want to revert...)

- By default migrate is an admin-only option. This could be changed by updating nova's policy.json -- taking this into account may be work for another, bigger blueprint though... The confirm/revert step isn't restricted to admins.